Effects of a fractional picosecond 1,064 nm laser for the treatment of dermal and mixed type melasma

Background: Picosecond laser is a novel modality for pigmented skin disorders with extremely short pulse duration. Little is known about the effects of the picosecond laser in melasma. Objective: This study aimed to investigate the efficacy of fractional picosecond 1,064?nm laser in melasma treatment. Study design: A prospective, randomized, assessor-blinded, intra-individual split face comparative study. Methods: Female subjects with melasma were enrolled and received fractional picosecond 1,064?nm laser plus 4% hydroquinone cream on one randomly assigned side of the face; the results were compared to the use of hydroquinone cream only on the contralateral side. The modified melasma area severity index (mMASI) score, melanin index by Mexameter MX18®, participant satisfaction score by quartile rating scale, and the quality of life by the dermatology life quality index (DLQI) were evaluated over 12 weeks. Results: Thirty female subjects completed the protocol. The mean (± standard deviation, SD) mMASI score at the 12-week visit was significantly reduced in the picosecond laser-treated areas compared to controls (3.52 ± 1.4 and 4.18 ± 2.03 respectively; p = 0.035). No differences were observed in the mean Mexameter melanin index, participant satisfaction score, and DLQI score. The observed adverse effects included transient mild erythema and mild skin desquamation. Conclusion: The addition of fractional picosecond 1,064?nm laser to 4% hydroquinone was effective and significantly better than 4% hydroquinone alone for the treatment of melasma.     

Metabolism of hyperpolarized 13C‐acetoacetate to β‐hydroxybutyrate detects real‐time mitochondrial redox state and dysfunction in heart tissue

Mitochondrial dysfunction is considered to be an important component of many metabolic diseases yet there is no reliable imaging biomarker for monitoring mitochondrial damage in vivo. A large prior literature on inter‐conversion of β‐hydroxybutyrate and acetoacetate indicates that the process is mitochondrial and that the ratio reflects a specifically mitochondrial redox state. Therefore, the conversion of [1,3‐¹³C]acetoacetate to [1,3‐¹³C]β‐hydroxybutyrate is expected to be sensitive to the abnormal redox state present in dysfunctional mitochondria. In this study, we examined the conversion of hyperpolarized (HP) ¹³C‐acetoacetate (AcAc) to ¹³C‐β‐hydroxybutyrate (β‐HB) as a potential imaging biomarker for mitochondrial redox and dysfunction in perfused rat hearts. Conversion of HP‐AcAc to β‐HB was investigated using ¹³C magnetic resonance spectroscopy in Langendorff‐perfused rat hearts in four groups: control, global ischemic reperfusion, low‐flow ischemic, and rotenone (mitochondrial complex‐I inhibitor)‐treated hearts. We observed that more β‐HB was produced from AcAc in ischemic hearts and the hearts exposed to complex I inhibitor rotenone compared with controls, consistent with the accumulation of excess mitochondrial NADH. The increase in β‐HB, as detected by ¹³C MRS, was validated by a direct measure of tissue β‐HB by ¹H nuclear magnetic resonance in tissue extracts. The redox ratio, NAD⁺/NADH, measured by enzyme assays of homogenized tissue, also paralleled production of β‐HB from AcAc. Transmission electron microscopy of tissues provided direct evidence for abnormal mitochondrial structure in each ischemic tissue model. The results suggest that conversion of HP‐AcAc to HP‐β‐HB detected by ¹³C‐MRS may serve as a useful diagnostic marker of mitochondrial redox and dysfunction in heart tissue in vivo.     

Occupational health education and collaboration for reducing the risk of lead poisoning of workers in a battery manufacturing plant in Thailand

We provided occupational health education as training to all workers (N=31) and managers, and collaborated with them against reducing the risk of lead poisoning of workers at an assembly section in a battery manufacturing plant in Bangkok, Thailand in 2002. After occupational health education, many workers (80.6-100.0%) noticed and understood the toxicity of lead and the importance of protection against it. Many workers regularly wore long sleeved shirt and trousers, and used the appropriate mask all day long. They changed the attitude toward their work and improved personal hygiene, for example no smoking in the workplace, washing their hands by a detergent before drinking water or having lunch, and taking a bath after the work. They especially took off working clothes at an office outside the workplace and washed them everyday. The average blood lead level of the workers significantly (P=0.002) reduced from 32.7 microg/dl to 22.4 microg/dl, although airborne lead level in the workplace remained unchanged with before conditions. From these results occupational health education and collaboration between workers and managers were effective tools to reduce the risk of lead poisoning of workers in a battery manufacturing plant.     

High frequency of mutation of epidermal growth factor receptor in lung adenocarcinoma in Thailand

Recent reports have suggested influences of racial difference on the frequency of mutation of EGFR in lung cancer. We therefore sought to characterize the frequency and pattern of mutation of EGFR in lung adenocarcinoma in Thai patients. Overall, EGFR catalytic domain mutations were detected in 35/61 (57.4%). We found 29/60 (48.3%) of exon 19 deletions, 5/54 (9.3%) of exon 21 point mutations, and 1/54 (1.9%) of double-mutation of both exons. The presence of these mutations was significantly associated with non-smoking habit. In summary, we report a strikingly high prevalence of mutation of EGFR in Thai lung adenocarcinoma, which may explain the high response rate to the treatment with TKI among Asian populations.